119 research outputs found
Is Progress 8 a valid and reliable measure of school effectiveness?
Policy-makers, school leaders, parents and citizens want to know whether schools are doing their job well, and whether particular schools or types of schools are doing that job particularly well. Insofar as the job is defined in terms of pupil attainment in public examinations, value added models are currently preferred. However, both the validity and reliability of value added models have been questioned and the debates about their fairness remain unresolved. One of the major problems for value added models is that while raw-scores for each school are reasonably stable over time the value added scores based on them are more volatile. This instability does not prove that there is a problem with the measures, but it is how construct irrelevant variance would manifest. This thesis addressed these concerns by scrutinising the validity of Progress 8, the Department for Education’s headline indicator of school performance in England. More specifically, it investigates whether the differences between schools’ annual performance ratings and the change in schools’ ratings over time can be explained by the kinds of factors that educational effectiveness is usually attributed to and perhaps more importantly, whether these factors are under the control of schools. The results show two things. First, that the Progress 8 scores are biased by external variables such as the differences in schools’ intake and examination entries. This is profoundly unfair and is likely to mean that the wrong schools are identified as differentially effective. And second, that even school leaders with expert knowledge of their institutions, access to students’ performance data and the previous year’s attainment averages cannot make reliable predictions about schools’ value-added results. This outcome invalidates the notion that parents can use Progress 8 outputs as a means of making informed decisions about the effect of their child attending one school over another
A Transition From Here to There?’ Neo-liberal Thought and Thatcherism
PhdThis PhD thesis asks how ‘neo-liberal’ was the Thatcher government? Existing
accounts tend to characterise neo-liberalism as a homogeneous, and often ill-defined,
group of thinkers that exerted a broad influence over the Thatcher government. This
thesis - through a combination of archival research, interviews and examination of
ideological texts - defines the dominant strains of neo-liberalism more clearly and
explores their relationship with Thatcherism. In particular, the schools of liberal
economic thought founded in Vienna and Chicago are examined and juxtaposed with
the initial neo-liberals originating from Freiburg in 1930s and 1940s Germany.
Economic policy and deregulation were the areas that most clearly linked neo-liberal
thinking with Thatcherism, but this thesis looks at a broad cross section of the wider
programme of the Thatcher government. This includes other domestic policies such as
education and housing, as well as the Thatcher government’s success in reducing or
altering the pressures exerted by vested interests such as the trade unions and
monopolies. Lastly, while less associated with neo-liberal theory, foreign policy, in
the area of overseas aid, is examined to show how ideas filtered into the international
arena during the 1980s. Although clearly a political project, the policies of
Thatcherism, in so far as they were ideological, resonate most with the more
expedient, or practical, Friedmanite strain of neo-liberalism. This encapsulated a
willingness to utilize the state, often in contradictory ways, to pursue more marketorientated
policies. As such, it sat somewhere between the more rules-based
ordoliberalism and the often utopian Austrian School
Local and landscape scale determinants of biodiversity and conservation value of macroinvertebrate assemblages in ponds across an urban land-use gradient
Urbanisation represents a growing threat to natural communities across the globe. Small aquatic habitats such as ponds are especially vulnerable and are often poorly protected by legislation. Many ponds are threatened by development and pollution from the surrounding landscape, yet their biodiversity and conservation value remain poorly described. Here we report the results of a survey of 30 ponds along an urban land-use gradient in the West Midlands, UK. We outline the environmental conditions of these urban ponds to identify which local and landscape scale environmental variables determine the biodiversity and conservation value of the macroinvertebrate assemblages in the ponds. Cluster analysis identified four groups of ponds with contrasting macroinvertebrate assemblages reflecting differences in macrophyte cover, nutrient status, riparian shading, the nature of the pond edge, surrounding land-use and the availability of other wetland habitats. Pond conservation status varied markedly across the sites. The richest macroinvertebrate assemblages with high conservation value were found in ponds with complex macrophyte stands and floating vegetation with low nutrient concentrations and little surrounding urban land. The most impoverished assemblages were found in highly urban ponds with hard-engineered edges, heavy shading and nutrient rich waters. A random forest classification model revealed that local factors usually had primacy over landscape scale factors in determining pond conservation value, and constitute a priority focus for management
Drought intensification alters the composition, body size, and trophic structure of invertebrate assemblages in a stream mesocosm experiment
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Intestinal parasites at the Late Bronze Age settlement of Must Farm, in the fens of East Anglia, UK (9th century B.C.E.).
Little is known about the types of intestinal parasites that infected people living in prehistoric Britain. The Late Bronze Age archaeological site of Must Farm was a pile-dwelling settlement located in a wetland, consisting of stilted timber structures constructed over a slow-moving freshwater channel. At excavation, sediment samples were collected from occupation deposits around the timber structures. Fifteen coprolites were also hand-recovered from the occupation deposits; four were identified as human and seven as canine, using fecal lipid biomarkers. Digital light microscopy was used to identify preserved helminth eggs in the sediment and coprolites. Eggs of fish tapeworm (Diphyllobothrium latum and Diphyllobothrium dendriticum), Echinostoma sp., giant kidney worm (Dioctophyma renale), probable pig whipworm (Trichuris suis) and Capillaria sp. were found. This is the earliest evidence for fish tapeworm, Echinostoma worm, Capillaria worm and the giant kidney worm so far identified in Britain. It appears that the wetland environment of the settlement contributed to establishing parasite diversity and put the inhabitants at risk of infection by helminth species spread by eating raw fish, frogs or molluscs that flourish in freshwater aquatic environments, conversely the wetland may also have protected them from infection by certain geohelminths
The effects of climatic fluctuations and extreme events on running water ecosystems
Most research on the effects of environmental change in freshwaters has focused on incremental changes in average conditions, rather than fluctuations or extreme events such as heatwaves, cold snaps, droughts, floods or wildfires, which may have even more profound consequences. Such events are commonly predicted to increase in frequency, intensity and duration with global climate change, with many systems being exposed to conditions with no recent historical precedent. We propose a mechanistic framework for predicting potential impacts of environmental fluctuations on running water ecosystems by scaling up effects of fluctuations from individuals to entire ecosystems. This framework requires integration of four key components: effects of the environment on individual metabolism, metabolic and biomechanical constraints on fluctuating species interactions, assembly dynamics of local food webs and mapping the dynamics of the meta-community onto ecosystem function. We illustrate the framework by developing a mathematical model of environmental fluctuations on dynamically assembling food webs. We highlight (currently limited) empirical evidence for emerging insights and theoretical predictions. For example, widely supported predictions about the effects of environmental fluctuations are: high vulnerability of species with high per capita metabolic demands such as large-bodied ones at the top of food webs; simplification of food web network structure and impaired energetic transfer efficiency; reduced resilience and top-down relative to bottom-up regulation of food web and ecosystem processes. We conclude by identifying key questions and challenges that need to be addressed to develop more accurate and predictive bio-assessments of the effects of fluctuations, and implications of fluctuations for management practices in an increasingly uncertain world
The application of graph theory and percolation analysis for assessing change in the spatial configuration of pond networks
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